Problems with Herbie

[diggler93]

Hello,

I just installed a CPR retro fit overflow box on my 120g. I did have a gl*******s but could just never make it quiet enough. Anyways, I have two 1.5" holes, one is my emergency which within the overflow is an upside down elbow and the other is the main drain which is a 90 with the opening on the bottom. Water flows out the back of the tank via 2 90 elbows into 1.5" flex pvc straight down into a 1.5" gate valve for the main. From there it goes down to my basement via flex PVC at an angle of about 45 degrees for approx 6', into a 45 degree elbow and straight into the sump.

The issue I'm having is that I'm getting air trapped in I believe the gate valve. If I turn off my return pump, then back on the water level in the overflow never returns to normal, and air is trapped in the gate valve. I can hear air trapped in the gate valve and unions and I just can't get it out. Not sure why it isn't flushing down into my sump. I'm not running any end pipe into the sump so the air should be able to escape.

Any help would be greatly appreciated.

 

[diggler93]

 

[jj5]

I would try ditching the elbows in the overflow. I have my main drain about 6 inches beloe the operating level. The overflow sets the level in the overflow and I have just a trickle going into it. The emergency overflow should make noise if any volume of water is getting sucked in. The main drain has to be far enough below the surface to restart the siphon and push the air out. Make sure the primary drain in the sump is just an inch or so below the surface. You should be able to purge the air for a full siphon.

 

[diggler93]

Ditched the one main drain elbow within the overflow. Still won't resume when the return is turned off. You can hear air in the gate valve gurgling. No idea how to make this flush it all out.

 

[Jone]

keep in mind where you handle on valve is set at,,,just twist the valve open almost a full turn for a couple of seconds and youll hear the air being purged,,after that is done,,twist the valve back to the original setting and your done..I do that all the time when i do water changes on my system when I power up the return pump..

 

[jj5]

Can you post a photograph of how the drains are set up on your overflow? It sounds like your still drawing air into the drain or the flow is insufficient to purge the air from the line.

 

[diggler93]

He overflow setup is very simple. Two bulkheads 1.5". One is now just a hole nothing added (main drain) the other is an upturned 90 for emergency. I did have a doe turned 90 on my main but removing it does seem to flush the air on startup better.

I'm trying to get to the point where a return pump start and stop requires no adjustment. With only 2 drains I think I'm limited on my design selections. I even considered in frustration switching to open pipe with silencers but I don't know if I could get it quiet so I stopped.

 

[jj5]

When my pump restarts after being shut down it takes about a minute or so to purge most of the air. It takes about three minuted for the overflow chamber to reach it's operating height. I make no adjustments during this time. How far below the surface of the water is the main drain when it's operating?

 

[Dross]

I think the gate valve should be down as close as possible to the sump in the basement. The high elevation above the sump creates a large negative pressure just downstream of the valve that causes air to degas and become trapped there. Just a new member with no experience with one, but that is my understanding from what I have read and understand about the drains.

 

[Vinny Kreyling]

Can't tell from the picture but the drain should not be more than 1" below the water level in the sump or you encounter back pressure. The emergency should be above the water line so it can be heard alerting you to a problem.